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On the Vertex Cover Number of 3-Uniform Hypergraph

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Journal of the Operations Research Society of China 2021年第2期9卷 427-440页

作者： zhuo diao School of Statistics and Mathematics Central University of Finance and EconomicsBeijing 100081China

Given a hypergraph H(V,E),a set of vertices S⊆V is a vertex cover if every edge has at least one vertex in S.The vertex cover number is the minimum cardinality of a vertex cover,denoted byτ(H).In this paper,we prove that for every 3-uniform connected hypergraph H(V,E),τ(H)≤2m3+1/3 holds on where m is the number of edges.Furthermore,the equality holds on if and only if H(V,E)is a hypertree with perfect matching.

关键词： 3-Uniform hypergraph Vertex cover Hypertree Perfect matching

Approximation Algorithms on k-Cycle Transversal and k-Clique Transversal

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Journal of the Operations Research Society of China 2021年第4期9卷 883-892页

作者： Zhong-Zheng Tang zhuo diao School of Science Beijing University of Posts and TelecommunicationsBeijing 100876China School of Statistics and Mathematics Central University of Finance and EconomicsBeijing 100081China

Given a weighted graph G=(V,E)with weight w:E→Z+,a k-cycle transversal is an edge subset A of E such that G−A has no k-cycle.The minimum weight of kcycle transversal is the weighted transversal number on k-cycle,denoted byτk(Gw).In this paper,we design a(k−1/2)-approximation algorithm for the weighted transversal number on k-cycle when k is odd.Given a weighted graph G=(V,E)with weight w:E→Z+,a k-clique transversal is an edge subset A of E such that G−A has no k-clique.The minimum weight of k-clique transversal is the weighted transversal number on k-clique,denoted byτapproximation algorithm for the weighted transversal number on k(Gw).In this paper,we design a(k2−k−1)/2-k-clique.Last,we discuss the relationship between k-clique covering and k-clique packing in complete graph Kn.

关键词： k-cycle transversal k-clique transversal Approximation algorithms

Therapeutic potential of TNFa inhibitors in chronic inflammatory disorders:Past and future

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Genes & Diseases 2021年第1期8卷 38-47页

作者： future Hongtao Zhang Nelson Shi zhuo diao Youhai Chen Yejia Zhang Department of Pathology and Laboratory Medicine Perelman School of MedicineUniversity of PennsylvaniaPhiladelphiaPAUSA Department of Orthopaedic Surgery Perelman School of MedicineUniversity of PennsylvaniaPhiladelphiaPAUSA Department of Physical Medicine&Rehabilitation Perelman School of MedicineUniversity of PennsylvaniaPhiladelphiaPAUSA Translational Musculoskeletal Research Center(TMRC) Corporal Michael J.Crescenz Veterans Affairs Medical CenterPhiladelphiaPAUSA

In the past 20 years,patients with rheumatoid arthritis(RA),Crohn’s disease(CD),and other immune diseases have witnessed the impact of a great treatment advance with the availability of biological TNFa inhibitors.With 5 approved anti-TNFa biologics on the market and soon available biosimilars,patients have more treatment options and have benefited from understanding the biology of TNFa.Nevertheless,many unmet needs remain for people living with TNFa-related diseases,namely some side effects and tolerance of current anti-TNFa biologics and resistance to therapies.Furthermore,common diseases such as osteoarthritis and back/neck pain may respond to anti-TNFa therapies at early onset of symptoms.Development of new TNFa inhibitors focusing on TNFR1 specific inhibitors,preferably small molecules that can be delivered orally,is much needed.

关键词： Antibodies Receptors Small molecule inhibitors TNFa TNFR1

Synthesis of Finite Molecular Nanotubes by Connecting Axially Functionalized Macrocycles

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CCS Chemistry 2022年第12期4卷 3772-3780页

作者： Liang-Liang Mao Hongyan Xiao Jin-Qin Zhao zhuo diao Wen Zhou Hongwei Li Chen-Ho Tung Li-Zhu Wu Huan Cong Key Laboratory of Photochemical Conversion and Optoelectronic Materials Technical Institute of Physics and ChemistryChinese Academy of SciencesBeijing 100190 Key Laboratory of Bio-Inspired Materials and Interfacial Science Technical Institute of Physics and ChemistryChinese Academy of SciencesBeijing 100190 School of Future Technology University of Chinese Academy of SciencesBeijing 100049 Beijing National Laboratory for Molecular Sciences College of Chemistry and Molecular EngineeringPeking UniversityBeijing 100871 Beijing NMR Center Peking UniversityBeijing 100871

Monodispersed molecular nanotubes,particularly those with uniform lengths,are challenging targets for chemical synthesis.Here,we report the general design and efficient synthesis of finite molecular nanotubes,utilizing a dynamic assembly strategy to precisely stack axially functionalized macrocycles by chemical connections.Discrete tubular molecules,ranging from 7.8 to 19.8 kDa with covalent or coordinative connections,have been prepared from modular macrocyclic building blocks through highly convergent routes.The discrete molecular nature and structural anisotropy of these synthetic tubes warrant postsynthesis modifications and solution processing methods,as demonstrated by the controllable orientations when deposited onto different prefabricated surfaces.

关键词： molecular nanotube dynamic assembly macrocycle covalence coordination

黄精炮制品多糖多元指纹图谱的建立及化学模式识别

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中草药 2024年第4期55卷 1124-1132页

作者：刁卓胡冲杨青山张亚中安徽医学高等专科学校安徽合肥230031 安徽省食品药品检验研究院安徽合肥230051 国家药监局中药质量研究与评价重点实验室安徽合肥230051 安徽中医药大学安徽合肥230012

目的构建黄精炮制品多糖的酶水解产物指纹图谱,结合化学计量学方法评价不同蒸晒次数黄精炮制品多糖的差异。方法采用糖苷酶水解,结合高效薄层色谱(high thin-layer chromatography,HPTLC)、亲水作用色谱-高效液相色谱-蒸发光检测器(hydr... 详细信息

目的构建黄精炮制品多糖的酶水解产物指纹图谱,结合化学计量学方法评价不同蒸晒次数黄精炮制品多糖的差异。方法采用糖苷酶水解,结合高效薄层色谱(high thin-layer chromatography,HPTLC)、亲水作用色谱-高效液相色谱-蒸发光检测器(hydrophilic interaction liquid chromatography-high performance liquid chromatography-evaporative light scattering detector,HILIC-HPLC-ELSD)和超高效液相色谱-四级杆飞行时间串联质谱(ultra high pressure liquid chromatographyquadrupole time of flight tandem mass spectrometry,UHPLC-QTOF/MS)对相应的酶解产物进行高效分离和检测。由此产生的自下而上的指纹图谱反映了黄精炮制品多糖的变化,通过相似度和偏最小二乘-判别分析(partial least squares-discriminant analysis,PLS-DA)对指纹图谱进行综合评价。结果HPTLC分析发现,果糖随着蒸晒次数的增加逐渐降低,结合色谱分析发现,六蒸六晒和十二蒸十二晒为黄精炮制过程中的转折点。同时根据酶水解中寡糖的变化,利用相似度和PLS-DA对不同蒸晒次数的黄精炮制品进行了清晰的聚类。结合UHPLC-QTOF/MS分析表明,不同蒸晒次数黄精炮制品中含有蔗糖、蔗果三糖、蔗果四糖、蔗果五糖、蔗果六糖、蔗果七糖及蔗果八糖。结论基于酶解法分析不同蒸晒次数样品的质量动态变化,结合所建立的多元指纹图谱,进一步阐释了不同蒸晒次数黄精炮制品的科学内涵。

关键词：黄精炮制品多糖酶解法指纹图谱质量控制化学模式识别 HPTLC HILIC-HPLC-ELSD UHPLC-QTOF/MS 偏最小二乘-判别分析寡糖蔗糖蔗果三糖蔗果四糖蔗果五糖蔗果六糖蔗果七糖蔗果八糖

HNTs@CeO_(2)-Au@Co_(3)O_(4)催化还原对硝基苯酚和染料污染物

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中国环境科学 2024年第1期44卷 193-201页

作者：方嘉声陈铭刁琪琪赵硕黄振庭卫昆卓琼芳东莞理工学院生态环境与建筑工程学院广东东莞523808 东莞市新污染物重点实验室广东东莞523808 山东理工大学化学化工学院山东淄博255049

制备了HNTs@CeO_(2)-Au@Co_(3)O_(4)核壳中空管状复合催化剂,用于还原降解水体中对硝基苯酚(4-NP)和染料(MB,MO)污染物.采用TEM,SEM,EDS,XRD,N_(2)吸脱附,XPS等方法对催化剂微观结构和物化特征进行表征.结果表明,CeO_(2)和Co_(3)O_(4)作为内外活性层较好地分散固载Au纳米颗粒,通过界面反应构筑于埃洛石纳米管中,形成CeO_(2)/Co_(3)O_(4)叠层结构封装埃洛石载金核壳复合催化剂(HNTs@CeO_(2)-Au@Co_(3)O_(4)).该催化剂分别在3.5,8和3min内可还原去除96%以上的4-NP,MB和MO污染物,其相应的一级反应动力学速率常数(0.856,0.370,1.337min^(-1))和转换频率(10.99,1.90,2.80min^(-1))均明显优于HNTs-Au@Co_(3)O_(4),HNTs@CeO_(2)-Au和HNTs@CeO_(2)@Co_(3)O_(4)对照材料.HNTs@CeO_(2)-Au@Co_(3)O_(4)催化剂连续进行6次使用后,仍保持较高的4-NP,MB和MO污染物还原转化率(91.2%,87.3%,89.5%)和结构稳定性.独特的CeO_(2)/Co_(3)O_(4)叠层结构特征和复合组分协同增强效应有效促进了高性能催化体系的构建,极大提升了Au颗粒的催化活性和稳定性,使HNTs@CeO_(2)-Au@Co_(3)O_(4)催化剂呈现较为优异的催化效能和循环使用性能.

关键词：纳米金催化剂埃洛石核壳结构对硝基苯酚染料污染物催化还原

基于酶解法和化学计量学的黄精多糖差异性分析

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药物分析杂志 2024年第2期44卷 324-332页

作者：刁卓胡冲杨青山张亚中安徽医学高等专科学校合肥230031 安徽省食品药品检验研究院国家药监局中药质量研究与评价重点实验室合肥230051 安徽中医药大学合肥230012

目的:建立糖苷酶水解下不同品种黄精多糖酶解产物的HPLC指纹图谱,探讨不同品种黄精多糖的差异,为黄精药材多糖质量评价提供参考。方法:黄精多糖经果糖苷酶水解后,采用HPLC建立黄精的指纹图谱;并结合相似度(SA)分析、聚类分析(HCA)和主... 详细信息

目的:建立糖苷酶水解下不同品种黄精多糖酶解产物的HPLC指纹图谱,探讨不同品种黄精多糖的差异,为黄精药材多糖质量评价提供参考。方法:黄精多糖经果糖苷酶水解后,采用HPLC建立黄精的指纹图谱;并结合相似度(SA)分析、聚类分析(HCA)和主成分分析(PCA),对指纹图谱进行分析,研究不同品种黄精多糖的差异。结果:不同品种黄精的多糖HPLC指纹图谱存在差异,共得到17个特异性寡糖片段,均含有果糖、葡萄糖和蔗糖。分析表明,3种基原黄精的种内指纹色谱相似度较高,差异较小,种间差异较大,而黄精混伪品与基原黄精差异明显。结论:不同品种黄精及其混伪品多糖酶解产物的指纹图谱结合化学计量学分析可以成功将黄精按照品种进行分类。所建立的HPLC方法简便、准确,重复性好,可用于黄精药材的多糖的差异研究。

关键词：黄精多糖酶解法指纹图谱差异化学计量学高效液相色谱法

Vegetation scattering attenuation characteristics of terahertz wave

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Journal of Systems Engineering and Electronics 2023年第6期34卷 1501-1507页

作者： JING Qingfeng diao zhuo ZHU Zhongbo College of Astronautics Nanjing University of Aeronautics and AstronauticsNanjing 210019China The 28th Research Institute of China Electronics Technology Group Corporation Nanjing 210000China The 504 Research Institution China Aerospace Science and Technology CorporationXi’an 710100China

A terahertz(THz)wave transmitted through vegetation experiences both absorption and scattering caused by the air molecules and leaves.This paper presents the scattering attenuation characteristics of vegetation in a THz range.The theoretical path loss model near the vegetation yields the average attenuation of THz waves in a mixed channel composed of air and vegetation leaves.Furthermore,a simplified model of the vegetation structure is obtained for generic vegetation types based on a variety of parameters,such as leaf size,distribution,and moisture content.Finally,based on specific vegetation species and different levels of air humidity,the attenuation characteristics under different conditions are calculated,and the influence of different model parameters on the attenuation characteristics is obtained.

关键词： terahertz(THz) scatter attenuation vegetation vegetation structure model

基于CiteSpace的国内外老年人认知衰弱可视化分析

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护士进修杂志 2024年第3期39卷 327-333页

作者：王黎平黎贵湘刘嘉怡刁艳君卓瑜四川大学华西医院/四川大学华西护理学院胰腺炎中心四川成都610041 四川大学华西医院/四川大学华西护理学院中西医结合科四川成都610041 四川大学华西医院/四川大学华西护理学院心理卫生中心四川成都610041

目的收集国内外老年人认知衰弱相关文献,分析其科研特征、发展趋势等,为今后该领域的研究提供一定参考。方法检索数据库Web of Science和中国知网于建库至2022年12月31日收录的相关文献,通过可视化软件CiteSpace对纳入文献进行图谱生... 详细信息

目的收集国内外老年人认知衰弱相关文献,分析其科研特征、发展趋势等,为今后该领域的研究提供一定参考。方法检索数据库Web of Science和中国知网于建库至2022年12月31日收录的相关文献,通过可视化软件CiteSpace对纳入文献进行图谱生成和数据分析。结果共文献纳入289篇,国际发文量最多的作者与机构均来自日本,中国则为发文量最多的国家。老年人认知衰弱的国际研究热点为患病率、不良影响、发病机制,国内研究热点为共病及影响因素等方面。该领域的发展趋势为认知衰弱的评估和干预。结论该领域国内外的研究热度正逐渐上升,虽然我国起步较晚,但后劲十足。研究机构或作者之间的合作较为分散,需要加强合作与交流。老年人认知衰弱的患病率、影响因素及共病是该领域的研究热点。未来该领域的发展趋势主要包括规范统一老年人认知衰弱量表在不同场景的应用,以及开展饮食、体育锻炼、心理关怀等干预方式的研究。

关键词：老年人认知衰弱护理可视化分析